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Re: Recent derailments - NTSB says Metro North too fast for curve 82 MPH
Author: Bruce Butler
Date: 12-03-2013 - 08:22
Interesting comments, especially from experienced railroaders like SP5103 and Shortline Sammie.
My operating experience is with relatively heavy grain trains at slow speed (10-20 mph) on a roller coaster railroad. I am amazed how quickly your speed can change if your attention is diverted for even a few seconds.
In the Metro North situation it does sound like the brakes dynamited when the derailment began. I would speculate that one possibility might be that the Engineer nodded off for a few seconds and woke up when violent rocking began as the train entered the curve. I have no experience with "blended" dynamic/air braking and will not comment on this aspect.
I have been involved in a few derailments and I love SP5103's definition: "I always thought if no one was killed or injured in the derailment or subsequent cleanup that it was a "succesful" derailment." Right on!!!
We have a significant descending grade which leads into a 10 degree curve with a 10mph speed limit. It would be a real ugly place to have a runaway! Most of the time the dynamics will keep the train under control although sometimes I need to use a little air to hold the speed where I want it. One night I was descending this grade with a long and heavy grain train when the dynamics suddenly faded to almost nothing! I quickly grabbed about 12# of air and we went around the curve OK. You don't have a lot of time to think about it before your speed starts to climb! As we started up the ascending grade out of the curve the engine died! Turned out that it was running out of fuel and the fading dynamics was the first indication. I knew that it was low but I didn't believe that it was THAT LOW!
My operating experience is with relatively heavy grain trains at slow speed (10-20 mph) on a roller coaster railroad. I am amazed how quickly your speed can change if your attention is diverted for even a few seconds.
In the Metro North situation it does sound like the brakes dynamited when the derailment began. I would speculate that one possibility might be that the Engineer nodded off for a few seconds and woke up when violent rocking began as the train entered the curve. I have no experience with "blended" dynamic/air braking and will not comment on this aspect.
I have been involved in a few derailments and I love SP5103's definition: "I always thought if no one was killed or injured in the derailment or subsequent cleanup that it was a "succesful" derailment." Right on!!!
We have a significant descending grade which leads into a 10 degree curve with a 10mph speed limit. It would be a real ugly place to have a runaway! Most of the time the dynamics will keep the train under control although sometimes I need to use a little air to hold the speed where I want it. One night I was descending this grade with a long and heavy grain train when the dynamics suddenly faded to almost nothing! I quickly grabbed about 12# of air and we went around the curve OK. You don't have a lot of time to think about it before your speed starts to climb! As we started up the ascending grade out of the curve the engine died! Turned out that it was running out of fuel and the fading dynamics was the first indication. I knew that it was low but I didn't believe that it was THAT LOW!
